Three week old chick, bruised foot?

I accidentally dropped the corner of the pvc pipe and chicken wire top of my grow-out pen into the pen yesterday and thought I had gotten lucky and missed all the babies. I apparently clipped my little RIR's foot with it because yesterday she was very lame, kept that foot lifted and tucked up, and was using her wing to help her move on that side. Today she is putting weight on her foot sometimes, and sometimes not.

The thing is, I don't *see* an obvious break, but there is a place on the top of her foot that is dark, same as if we had a bad bruise. I guess chickens can get bruises, right? Do you (much more experienced) chicken folk think she will heal on her own? She is moving around and she was right there with the rest of the flock when they had their scrambled eggs for breakfast this morning. She does seem to lie down a bit more than normal, but maybe that is mother nature telling her to rest her injured footsie? I feel horrible, and I'm fortunate that nobody got any more injured. If there is anything I need to do for Lucy, please post! Thanks so much